Sensitizing composition for photographic paper.



FRANK IRVING RUBRICIUS).

ants union OF HEW YGEK, N. Y.

SENSITIZING COMPOSITION FOR PHOTOGRAPHIC PAPER.

No Drawing.

To all whom it may cone-em Be it known that I, FRANK I. Russians, a citizen of the United States, and a resident of the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Sensitizing Compositions for Photographic Paper, of which the following is a specification.

This invention relates to sensitizing preparations for use in photography, and has for its object the preparation of a sensitizi-ng agent that may be used to sensitize thinner,or more nearly transparentpapers than it has heretofore been possible to sensitize with the preparations available, such paper, for instance, as Japanese tissue paper. Such papers are sufliciently transparent to permit the paper upon which they are mounted to show through them, thereby making it possible to produce any toxic desiredby simply using a suitable color for the mount. Prints made upon such thin paper may also be glued upon glass plates for use as lantern slides. In such instances the print upon the glass may be suitably colored. This is a great saving over the prevalent method of producing each lantern slide from a sensitized plate, for with my sensitized tissue paper, only plain glass is necessary. A further advantage of such,

sensitized paper is the velvety appearance it presents. On account of this velvety ap-. pearance coarse retouching of-the negative doesfnot show upon it.

A further advanta e of my invention consists in the simpli ed manner in which paper sensitized with my preparation is developed, toned and fixed, thereby saving time and money that would otherwise be expended for chemicals if the existing methods were pursued.

In carrying out the invention in its most pref rred manner four solutions are prepared for the sensitizing agent, as follows: The first solution is composed of ferric ammonium citrate, (green scales) 150 grains,

preferably powdered gum arabic 15 grains and distilled water 1 ounce. The second solution is composed of citric acid 60 grains Specification of Letters Patent.

a hypo bath, thereby producing a material Patented Feb. 2, 1915.,

Application filed May 31, 1913. Serial No. 770,962.

and distilled Water l-ounce. Thethird solution is formed of silver nitrate grains and distilled water 1 ounce, and the fourth solution is composed of uranium nitrate 20 grains and distilled water 1 ounce. After the ingredients of these solutions are dissolved the solutions are intermixed-in the, order above given, after which 30 drops of valcohol are added, care heingtaken that the preparation is continuously stirred as the co difierent solutions and alcohol are added.

The sensitizing preparation as thus formed may be used upon the paper or other material commonly used in photography and is not limited to any particular sizing that may be applied upon the paper or other material: With my invention tissue papers may be sensitized which it has been impossible to sensitize with preparations heretofore used, thereby producing a new style of? paper which on account of its transparency and velvety surface is capable of many uses to which other papers cannot be put.

i prefer to use a sizing composed of Bermuda arrow-root grains which is dissolved in 2 ounces of distilled cold water, after which 30 ounces ,of boiling water is added. To this solution is added glucose 20 grains and sodium phosphate dibasic 55 grains. .This resultant solution is boiled for about two mirutes during which time it is stirred and then strained. The sizing thus formed is applied preferably by floating or immersing the paper or other material therein While warm, after which it is remo ed and quickly dried.

Paper containing my sensitizing preparation is developed and toned by the use of water only. It is fixed by the use only oi? saving in time and money.

lVhile'I have described the carrying out of my invention in its most preferred man ner I do not wish to limit the scope thereof to the particular ingredients and propor tions herein set forth. for the various unalogue's of said ingredients may be substituted and different proportions may be used within certain limits without departing from the substance of this invention.

2 v mms'm Having thus described my invention I In testimony whereof Ihave herexihto set claim I my hand in the resence of two witnesses. A sensltlzmg pgeparatwn {qr use inphe- FRANK IRVING Humming togmphy contalmng a solutlon of fen-1c 5 ammonium citrate (green scales), gum ara- Witnesses:

.bic, citric acid, silver nitrate, uranium ni- S. THORNTON, tmte, and alcohol substantially as described. 0, B, KING. 

